Why is CNN still allowing Mark Williams on its network?

Just how racist does Mark Williams have to be before CNN will refuse to invite him on its network?

Williams has a long history of incendiary and racially charged remarks. CNN knows about this-- heck, Anderson Cooper called him out on it last September. But it has never stopped CNN from repeatedly inviting him on.

Williams wrote a July 15 blog post in which he not only attacked the National Association for the Advancement of Colored People for the use of "colored people" in its name as racist -- an idea he also promoted in an appearance on the July 14 edition of CNN's The Situation Room, in a debate with Roland Martin -- he also portrayed blacks as lazy and NAACP leader Ben Jealous as supporting the repeal of civil-rights laws so that "massa" would again take care of blacks: "As Coloreds we must have somebody care for us otherwise we would be on our own, have to think for ourselves and make decisions!"

You'd think that would be a sign that Williams is not someone who should be invited on CNN. You'd be wrong.

John King led his July 16 edition of John King USA with an interview of Williams to defend himself. Williams, of course, never really apologized for the post; rather, he seemed proud of it, touting how it was "successful" in "slap[ping] some sense into a lot of people." Nevertheless, King invited Williams on again if accompanied by Jealous to have a "civil conversation about what divides the two of you." Never mind that Williams has exhibited little evidence of being able to hold such a "civil conversation."

Repeat: King led his show with this.

Then, in a discussion of Williams' blog post on the July 17 edition of CNN Newsroom, anchor Don Lemon announced that Williams would appear on CNN again today to explain himself.

Why does Williams deserve two -- let alone any -- opportunities to come on CNN and discuss his incendiary blog post? Has CNN ever extended such a courtesy to a liberal who made controversial claims?

Most news outlets would have interpreted Williams' record of offensive remarks as a warning against ever allowing him on. CNN, however -- apparently operating under an exemption to its supposed dictate to not book radio hosts -- seems to think those remarks are a reason to mainstream him.

UPDATE: The National Tea Party Federation announced on today's edition of CBS' Face the Nation that Williams and the group he represents, the Tea Party Express, has been expelled from the federation. If Williams' own fellow tea partiers no longer want anything to do with him, why does CNN?

UPDATE 2: Williams didn't make the second appearance -- but only because he canceled it. Before the scheduled appearance, according to anchor Don Lemon, Williams sent an email to CNN saying, "Sorry, have to cancel, traveling plans changed last minute." In his stead, Lemon had on the National Tea Party Federation's David Webb, who called Williams "an embarrassment" and "toxic."